I've got some muck boots, they are the warmest boots I've ever had and are very comfortable for walking and plodging through rock pools. They are fine to wear in the summer too as the lining wicks the sweat away and keeps your feet cool. The only downside is that the soles wear out more quickly than other boots, they must be a softer rubber. I have worn mine smooth after about eighteen months but they get a hell of a lot of use and I will be buying another pair to replace them.